#coding=utf8
from Tkinter import *
import time


class StopWatch(Frame):
    '''實現一個秒錶部件'''
    msec = 100
    def __init__(self, parent=None, **kw):
        Frame.__init__(self, parent, kw)
        self._start = 0.0
        self._elapsedtime = 0.0
        self._running = False
        self.timestr = StringVar()
        self.makeWidgets()
    def makeWidgets(self):
        '''製作時間標籤'''
        l = Label(self, textvariable = self.timestr)
        self._setTime(self._elapsedtime)
        l.pack(fill = X, expand = NO, pady = 2, padx = 2)
    def _update(self):
        self._elapsedtime = time.time() - self._start
        self._setTime(self._elapsedtime)
        self._timer = self.after(self.msec, self._update)
    def _setTime(self, elap):
        '''將時間格式改為 分：秒：百分秒'''
        minutes = int(elap/60)
        seconds = int(elap-minutes*60.0)
        hseconds = int((elap - minutes*60.0 - seconds) *100)
        self.timestr.set('%2d:%2d:%2d' %(minutes, seconds, hseconds))
    def Start(self):
        if not self._running:
            self._start = time.time() - self._elapsedtime
            self._update()
            self._running = True
    def Stop(self):
        '''停止秒錶'''
        if self._running:
            self.after_cancel(self._timer)
            self._elapsedtime = time.time() - self._start
            self._setTime(self._elapsedtime)
            self._running = False
    def Reset(self):
        '''重設秒錶'''
        self._start = time.time()
        self._elapsedtime = 0.0
        self._setTime(self._elapsedtime)
        
        
if __name__ == '__main__':
    def main():
        root = Tk()
        sw = StopWatch(root)
        sw.pack(side = TOP)
        Button(root, text = 'start', command = sw.Start).pack(side = LEFT)
        Button(root, text = 'stop', command = sw.Stop).pack(side = LEFT)
        Button(root, text = 'reset', command = sw.Reset).pack(side = LEFT)
        Button(root, text = 'quit', command = root.quit).pack(side = LEFT)
        root.mainloop()
    main()